Earthing

[Guest]

Hey all,

I looked at a V7 sti yesterday and it was fully standard except for extra wires linked from the negative battery terminal to different points in the car. Car dealer said it was extra earthing and was no big deal.

Can someone please enlighten me as to why this would need to be done. (to a standard V7 sti).

[DRFVDR]

Different thoughts on this

some say it helps

some say it for looks

I say it helps gives the sensors a better earth

which feeds the ecu a better signal

hopefully makes it run smoother

if it good enuff for STi to do then whose to argue

[Joker]

http://homepages.ihug.co.nz/~ccgrant/earth.htm

Its generally accepted it cant do any harm

although some have claimed "rough" idle after applying this mod

[pl0x]

 Joker said:

http://homepages.ihug.co.nz/~ccgrant/earth.htm

Its generally accepted it cant do any harm

although some have claimed "rough" idle after applying this mod

What you mean be rough ilde? i cant rember when mine started idling weird, but i have done this mod, i found it to do nothing at all

[Guest]

 

The Grounding "Mod" is junk or not depending on whether your car is grounded well or not.

Let's start with the simple fact that the car has a grounding wire system in place - it's attached to the manifold. Now, before the current WRX, or in Japan, before the Legacy Rev. D, there was roughly 1/4 the amount of wiring used in grounding the car's systems as there is now. Between the outbreak of the grounding mod in Japan and the current Subaru models, Subaru themselves decided to upgrade the wiring.

Because of this upgrade by the factory, the results of the grounding modification on a new Subaru are minor in comparison of the grounding on older Subaru's. There's 3 different revisions of Legacy B4 twin turbo's that we've got on hand, and the results of the mod between the A and B revision compared to the D revision vary wildly. It has a large effect on the A and B revision models, very little on the D (no C available for testing).

If the grounding modification *does* have a large effect, it's because the factory system isn't doing it's job, and that can be from a variety of causes - old age is always a major factor. A poor connection at one point in the system may or may not effect things. The grounding mod will help this point, but you could probably do away with the grounding mod by simply cleaning up all your current grounding connections and making sure they are properly tightened down. Of course, there's a lot of wires under there..

The reason it's could be snake oil for some people is simple - it is, for their cars. It's not a 100% guaranteed-to-work modification, since it's simply helping an already present system that may actually be doing it's job, especially with the new WRX's and other Subaru's with their beefed-up factory systems.

And the point isn't that you are gaining something over any other stock WRX with this modification - if they are just fine from the factory, you are simply bringing your car up to within standard operating parameters.

OTOH, if you own a older GC8 WRX or STi, twin-turbo Legacy, Lancer Evolution and such, it may have major benefits mainly because of the age of these vehicles. Of course, the major benefit is to bring it up to spec output, but when you've got an older car, that's good enough!

Cheers,

Paul Hansen

[Joker]

 pl0x said:

What you mean be rough ilde? i cant rember when mine started idling weird, but i have done this mod, i found it to do nothing at all

same here - but it has been reported (in the old forum version of this thread)

[pl0x]

 Joker']

[quote name='pl0x said:

What you mean be rough ilde? i cant rember when mine started idling weird, but i have done this mod, i found it to do nothing at all

/quote]

same here - but it has been reported (in the old forum version of this thread)

Hmm mite have to take it off and see if the idle comes right? i was just going to leave it on as its not doing any harm on there

[Guest]

Easy to check with multi meter.

Set to Mv scale and measure voltage between intake manifold and battery earth post

MAX 150Mv, if higher clean your earths or fit earthing kit

As already posted minor Mv will porbably not casue any issue

However the higher the Mv reading you get the less acurate your engine senors become

It's a good check and I trained all my tech's to check this on every car that came in to the shop. Takes 10sec max

As for inducing an idle fault, BS. As the car obviosly had a fault before hand that the ECM had compenstated for it

The ECM will re adjust again but easier to ECM reset.

[Pappu1]

i just managed to install a HKS super grounding system - purple lol..

anyway, it makes no difference as far as i can tell but looks good in the the engine bay.

im going to keep it just for show/wow factor anyway.

[Guest Rugged_RS]

its not a bad thing but chances are if your standard earthing has been deterriorated then it will help, if its just the same nice an clean points tidy wires etc then its not gonna make a difference to your car